Standardize usage of virtual/override/final in chrome/browser/media

chrome/browser/media/fake_desktop_media_list.h

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_MEDIA_FAKE_DESKTOP_MEDIA_LIST_H_
 #define CHROME_BROWSER_MEDIA_FAKE_DESKTOP_MEDIA_LIST_H_
 
 #include <vector>
 
 #include "chrome/browser/media/desktop_media_list.h"
 
 class FakeDesktopMediaList : public DesktopMediaList {
  public:
   FakeDesktopMediaList();
-  virtual ~FakeDesktopMediaList();
+  ~FakeDesktopMediaList() override;
 
   void AddSource(int id);
   void RemoveSource(int index);
   void MoveSource(int old_index, int new_index);
   void SetSourceThumbnail(int index);
   void SetSourceName(int index, base::string16 name);
 
   // DesktopMediaList implementation:
-  virtual void SetUpdatePeriod(base::TimeDelta period) override;
-  virtual void SetThumbnailSize(const gfx::Size& thumbnail_size) override;
-  virtual void SetViewDialogWindowId(
-      content::DesktopMediaID::Id dialog_id) override;
-  virtual void StartUpdating(DesktopMediaListObserver* observer) override;
-  virtual int GetSourceCount() const override;
-  virtual const Source& GetSource(int index) const override;
+  void SetUpdatePeriod(base::TimeDelta period) override;
+  void SetThumbnailSize(const gfx::Size& thumbnail_size) override;
+  void SetViewDialogWindowId(content::DesktopMediaID::Id dialog_id) override;
+  void StartUpdating(DesktopMediaListObserver* observer) override;
+  int GetSourceCount() const override;
+  const Source& GetSource(int index) const override;
 
  private:
   std::vector<Source> sources_;
   DesktopMediaListObserver* observer_;
   gfx::ImageSkia thumbnail_;
 };
 
 #endif  // CHROME_BROWSER_MEDIA_FAKE_DESKTOP_MEDIA_LIST_H_